How Is Decaf Coffee Made? Processes, Caffeine and Choosing Beans
|
|
Time to read 5 min
Quick answer: decaf coffee is made by removing most of the caffeine from green, unroasted coffee beans before they are roasted. The best choice is not simply one process: origin, roast level, freshness and how you brew all shape the cup. At Redber, our current roasted range uses Swiss Water®, Mountain Water and CO₂ decaffeination.
What is decaf coffee?
Decaf starts as ordinary green coffee. Before roasting, the beans go through a process that removes most of their naturally occurring caffeine. They are then roasted and brewed in the same way as regular coffee.
Decaf does still contain a small amount of caffeine, so “decaffeinated” should not be read as “caffeine-free”. The exact amount in a cup varies with the bean, process, dose and brewing method. For most shoppers, the useful point is that decaf provides the familiar coffee ritual with much less caffeine than regular coffee.
How is caffeine removed from coffee?
Caffeine is soluble, so processors can draw it out of hydrated green beans. The process has to be selective: coffee contains many other soluble compounds that contribute aroma, sweetness, acidity and body. Modern methods use water and filtration, pressurised carbon dioxide, or a food-grade solvent to separate caffeine while retaining as much of the coffee’s original character as possible.
The decaffeination method matters, but it cannot create quality that was not present in the green coffee. Good sourcing, careful storage, an appropriate roast and freshness after roasting remain just as important.
Decaf processes compared
| Process | How it works | Redber range |
|---|---|---|
| Swiss Water | Water, temperature, time and carbon filtration; no added chemical solvents. | Colombia, Guatemala and Peru. |
| Mountain Water | Water-based extraction and filtration carried out by Descamex in Mexico. | Colombia Medellín and Mexico. |
| CO₂ | Pressurised carbon dioxide selectively attracts caffeine. | Central American blend. |
| Sugarcane / EA | Ethyl acetate removes caffeine from hydrated green beans. | Not in our current live roasted range. |
Swiss Water Process
Swiss Water is a water-based method developed as an alternative to solvent decaffeination. The processor uses water, temperature, time and carbon filtration. A caffeine-free green coffee extract helps draw caffeine out of a new batch of beans while limiting the movement of other soluble coffee compounds. Carbon filters capture the caffeine, and the cycle continues until the target is reached.
Choose Swiss Water if you want a process without added chemical solvents or if you enjoy comparing the character of several origins processed in the same way. Redber currently offers Swiss Water coffees from Colombia, Guatemala and Peru.
For a lighter, cleaner cup, try Guatemala Swiss Water Medium Roast. For more body, compare Guatemala Medium-Dark, Colombia Medium-Dark and Peru San Martin Medium-Dark.
Mountain Water Process
Mountain Water is also a water-based decaffeination method, but it is a separate process operated by Descamex in Mexico. The green beans are prepared with water so that caffeine and other soluble compounds can move out of the bean. Filtration removes caffeine, while flavour-rich liquid is managed so the coffee retains its character.
An older version of this guide incorrectly said Mountain Water processing took place in Colombia. The process is carried out in Mexico. The coffee itself can come from other origins, which is why our range includes both a Mexican single-estate coffee and a Colombian coffee from the Medellín area.
Choose Colombia Medellín Medium-Dark for chocolate, caramel and toasted-nut character. Choose Colombia Medellín Dark or Mexico Mountain Water Dark for a deeper espresso-style cup.
CO₂ decaf process
In the CO₂ method, hydrated green beans are held in a pressurised chamber. Carbon dioxide circulates through them and selectively attracts caffeine. The caffeine is separated from the CO₂, which can be reused within the system.
CO₂ processing can support a full-bodied cup, making it a useful match for darker espresso styles. Redber’s Central American Medium Roast is smooth and balanced, while the Dark Roast brings out dark chocolate, cinnamon and warming spice.
What about sugarcane decaf?
Sugarcane decaf is a common name for ethyl acetate or EA processing. Ethyl acetate can occur naturally, including in fruit, and the process is often associated with coffees decaffeinated close to origin in Colombia. The hydrated beans come into contact with an EA solution that attracts caffeine, after which they are rinsed and dried.
Sugarcane decaf can taste excellent, but it is not part of Redber’s current live roasted range. We have therefore removed the old link that sent readers to an unpublished product.
How to choose the best decaf coffee for you
1. Choose by flavour
- Chocolate-led and rich: Central American Dark, Colombia Medellín Dark or Mexico Dark.
- Balanced and rounded: Colombia Medellín Medium-Dark, Colombia Swiss Water, Guatemala Medium-Dark or Peru Medium-Dark.
- Cleaner and gentler: Central American Medium or Guatemala Medium.
2. Choose by roast
A medium roast keeps more brightness and is often a good fit for filter, AeroPress and cafetière. Medium-dark offers a balance of body and clarity. Dark roast brings deeper chocolate and spice, making it an easy starting point for espresso, bean-to-cup machines and milk drinks.
3. Choose by brew method
There is no rule that restricts a coffee to one brewer. Start with the recommendations below, then adjust grind size, dose and time to taste:
- Espresso and bean-to-cup: medium-dark or dark roast.
- Filter and V60: medium or medium-dark roast.
- Cafetière: any roast, using a coarse grind.
- AeroPress: medium or medium-dark is a flexible starting point.
Redber decaf coffee range
- Central American CO₂ Decaf – Medium Roast
- Central American CO₂ Decaf – Dark Roast
- Colombia Medellín Mountain Water – Medium-Dark Roast
- Colombia Medellín Mountain Water – Dark Roast
- Colombia Swiss Water – Medium-Dark Roast
- Guatemala Swiss Water – Medium Roast
- Guatemala Swiss Water – Medium-Dark Roast
- Mexico Mountain Water – Dark Roast
- Peru San Martin Swiss Water – Medium-Dark Roast
All are available as whole beans, with ground options shown on each product page. You can also set up a decaf coffee subscription or browse unroasted decaf green coffee.
Frequently asked questions
Is decaf coffee caffeine-free?
No. Decaffeination removes most caffeine, but a small amount can remain. The amount in the cup depends on the coffee and how it is brewed.
Does decaf coffee taste different?
It can, because processing and roasting both affect flavour. Modern decaf made from good green coffee can still be sweet, balanced and full-bodied. Freshness and grind size matter just as much as they do for regular coffee.
Which decaf process is best?
There is no universal winner. Swiss Water and Mountain Water suit shoppers looking for water-based processing, while CO₂ can produce a full-bodied result. Choose the coffee whose origin, roast and tasting notes match your preferences.
Is Swiss Water the same as Mountain Water?
No. Both are water-based, but they are separate branded processes run by different companies. Swiss Water operates its own process; Mountain Water is operated by Descamex in Mexico.
What is the best decaf for espresso?
Start with a medium-dark or dark roast. Colombia Medellín Dark, Mexico Mountain Water Dark and Central American Dark have the body to work well as espresso and through milk.
Should I buy whole-bean or ground decaf?
Whole beans are best if you own a suitable grinder because you can grind immediately before brewing. If you do not have one, choose the ground option that matches your brewer.
How should I store decaf coffee?
Keep it sealed, cool and dry, away from heat, moisture and strong odours. Buy a quantity you can use while fresh rather than storing an open bag for a long time.
